Transverse car body conveying system

ABSTRACT

A skid-type car body carrier carries a transversely oriented car body along a conveying path. The carrier is driven by a drive roller which frictionally engages a centrally located friction bar mounted underneath the carrier.

FIELD OF THE INVENTION

This invention relates to a transfer system for conveying car bodies ina factory, and more specifically to a transverse car body conveyingsystem, in which a skid-type carrier travels passively on rails, and onwhich a car body mounted on the carrier is oriented in a directiontransverse to the direction of carrier movement.

BACKGROUND OF THE INVENTION

Known car body conveying systems include systems having a number ofconveyor units, in which a large number of hybrid conveying carrierstravel. Each conveying carrier is provided with left and right conveyingskids, left and right front wheels, and left and right rear wheels. Thehybrid type carriers are propelled by driving rollers and controlled bya large number of carrier-detecting sensors.

As shown in FIG. 8, a conventional hybrid-type storage conveyor system,disclosed in Japanese Laid-Open Patent Publication 2001-63555, isarranged in a C-shaped configuration, and comprises two conveyor tracks200 connected by a traverser mechanism T for transferring car bodies Wfrom one of the two conveyor tracks to the other. On the conveyortracks, the car bodies are conveyed in the longitudinal direction of thebodies. The lengths of the conveyor tracks 200 need to be sufficientlylarge to accommodate the car body lengths w1, and consequently storageefficiency is low. Moreover, the carrier size is necessarily large,resulting in high carrier weight and a high conveying power requirement.

In a conveyor system in which all of the carriers are identical, inorder to accommodate various car bodies of different lengths, the lengthL2 of each of the carriers must correspond to the length of the longestcar body with which the conveyor system is to be used. Consequently, thelengths of the carriers impose a limit on the number of carriers thatcan be provided along each track 200. Furthermore, in some cases, it hasbeen necessary to replace carriers on the conveyor system with newcarriers in order to accommodate different car bodies.

In the conventional hybrid type storage conveyor of FIG. 8, a door of acar body W can open unexpectedly as a result of vibration, or impactsuch as may occur when carriers come into contact with each other.Opening of a car door during operation of the conveyor can cause damageto objects adjacent to the conveying path, as well as injury topersonnel. To prevent damage and injury, ropes R were provided alongboth sides of the conveyor to limit opening of the doors. However, theseropes take up space, and become an obstacle to various operations,impairing productivity.

Accordingly, objects of this invention are to overcome theabove-mentioned problems of a conventional conveying system; to reducethe size and weight of a skid-type carrier; to make a skid-type carrieradaptable to various types of car bodies, thereby improving itsversatility; and to prevent accidental opening of the doors of the carsbeing conveyed without requiring additional space, and without impairingproductivity.

SUMMARY OF THE INVENTION

The car body conveying system in accordance with the invention comprisesa pair of rails extending in spaced, parallel relation to each otheralong a conveying path. A skid-type carrier is supported on the railsfor travel along the conveying path. Brackets mounted on the carrier arearranged to support an elongated car body on the carrier, with thedirection of elongation of the car body extending transverse to thedirection of travel of the carrier along the conveying path. A frictionbar, supported by said carrier, extends along the direction of travel ofthe carrier along the conveying path, and a drive roller disposed on theconveying path is positioned to engage, and impart a frictional drivingforce to, the friction bar.

Preferably, the length of the friction bar is greater than the maximumwidth of the car body mounted on the carrier, but less than the lengthof the car body, and the friction bar and drive roller are preferablylocated along a center line midway between the rails. Dooropening-prevention barriers, provided at front and rear positions on thecarrier, are positioned to engage doors of the car body supported on thecarrier in order to limit opening thereof.

The car body conveying path to which the transverse car body conveyingsystem of the invention is adapted can be a conveying line for conveyingcar bodies in an assembly step, a painting step, a drying step, or thelike in a car factory, for example. The term “car body” should beunderstood to refer either to a fully assembled car, or a partialassembly comprising at least the car's body shell, or its chassis.

The skid-type carrier has a car body mounted thereon in transverseorientation with respect to the direction of carrier travel along theconveyor path, and is passively propelled along a pair of rails by africtional driving force imparted by a drive roller. The friction bar,which extends along the direction of carrier travel, can be much shorterthan the front-to-rear dimension of the car being transported. The sizeof the skid-type carrier can be relatively small compared to theconventional carrier, and consequently a high storage efficiency can berealized. Moreover, the power required to propel the carrier along theconveying path is substantially lower than the power required in aconventional conveyor. Moreover, since different types of car bodiesgenerally do not differ greatly in their widths, the carrier can becompatible with a wide variety of car bodies.

Because the friction bar and the driving roller are provided on thecenter line of the car body conveying path, stable travel of the carriercan be attained, and the frame of the skid-type carrier can bestructurally very simple.

Furthermore, because door opening-preventing barriers are provided atfront and rear positions along the conveying direction of the carrierframe, it is unnecessary to provide conventional door opening-preventionropes on both sides of the car body conveying path. Consequently, morespaces is provided along both sides of the conveying path for variousoperations, such as painting, assembly, etc.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic layout of a transverse car body conveying systemin accordance with a first embodiment of the invention;

FIG. 2 is a plan view showing details of the transverse car bodyconveying system of FIG. 1;

FIG. 3 is an elevational view of the transverse car body conveyingsystem as shown in FIG. 2;

FIG. 4 is a side view of the transverse car body conveying system ofFIG. 1;

FIG. 5 is an enlarged side view showing a skid-type carrier used in theconveying system of FIG. 1;

FIG. 6 is a side view of a friction roller type drive used in theconveying system;

FIG. 7 is a side view of a modified friction roller drive; and

FIG. 8 is a schematic layout view of a conventional car body conveyingsystem.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the transverse car body conveying system shown in FIG. 1, car bodiesmay be transported along conveying path X1 in a painting step, and alongconveying path X2 in a drying step. The car bodies are transferred alonga conveying path X3 from passage X1 to passage X2 by a traversermechanism T. Each of the car bodies is arranged so that its direction ofelongation, i.e., its long dimension, is in transverse relationship toits direction of travel along passages X1 and X2, and the entireconveying system of FIG. 1 is generally C-shaped in plan view.

Skid-type carriers 110 for mounting the transversely oriented car bodiesW, travel passively on a pair of left and right rails 130 provided alongconveying paths X1 and X2. The carriers are propelled by driving forcesimparted by friction drive rollers located along each of the car bodyconveying paths X1 and X2. The drive roller mechanism 120 for conveyingpath X1 is shown in FIG. 1.

The skid-type carrier 110 as shown in FIGS. 2 to 5 includes arectangular carrier frame 111 for mounting the car body in atransversely oriented condition relative to the rails 130, and supportbrackets 112, which are located on the top of the carrier frame 111adjacent the left front, right front, left rear and right rear cornersof the frame, and which secure and support the car body W on the frame.Wheels 113 which are also mounted rotatably on the frame adjacent thecorners of the frame, travel on rails 130 and support the frame and thecar body mounted thereon. A transfer lifter Z, shown in FIG. 4 is usedto transfer the skid-type carrier 110.

A friction bar 114, which comes into contact with the drive roller, isalso mounted on the underside of the frame. The friction bar 114 ispositioned on the center lines CL of the car body conveying paths X1 andX2. Consequently it can come into contact with the drive rollermechanism 120. The skid-type carriers 110 can travel in a stable manner,the structure of the carrier 110 is simple, and the number of driveroller mechanisms 120 required along conveying paths X1 and X2 iscomparatively small.

The length of the friction bar need only be slightly greater than thewidth w2 of the car body, and can be much shorter than the car bodylength w1. Because the widths of the carriers is reduced, more of themcan fit along a conveyor passage of a given length. Consequently,improved storage efficiency can be realized. Additionally, even in thecase of car bodies W having differing widths w2, the differences betweenthe body widths is generally very small. Therefore, a given skid-typecarrier 110 configured to carry a car body in transverse orientation,can be easily adapted to a variety of car bodies, and consequently ahigh degree of compatibility and versatility in the skid-type carrier110 can be realized.

As shown in FIG. 5, door opening-prevention barriers 115 arerespectively provided on the skid-type carrier 110 at positions near thefront and rear doors on both sides of the car body W mounted on thecarrier frame 111. It not necessary to provide a door opening-preventionrope on both sides of the conveying paths as in the conventionalconveyor system depicted in FIG. 8. The absence of ropes providesinterference with operating space on both sides of the conveying pathsX1 and X2.

As shown in FIG. 6, the friction roller drive mechanism 120, includes apolyurethane friction roller 121, which contacts the friction bar 114 ofthe skid-type carrier 110, and a support frame 122 attached to a frameof a car body conveying path X1 or X2. A biasing device 123 presses theroller 121 upward against the bar 114. In a modified drive mechanism asshown in FIG. 7, a friction roller drive 120 includes a polyurethaneroller 121, which is pressed upwardly by an air bellows 124 intoabutting relationship with bar 114 on a carrier 110.

In summary, because the skid-type carrier 110 is arranged to carry carbodies oriented in a direction transverse to their direction of travelon the conveyor path, the size of the carrier can be reduced, and lesspower is required to move the carriers. The lengths of the friction bars114 can be reduced to a length which corresponds to the car body widthw2, and which is shorter than the car body length w1, and consequently alarger number of car bodies can be accommodated in a conveyor of a givenlength. Additionally, different types of car bodies can be accommodatedby a given skid-type carrier 110, and therefore the conveyor has agreater versatility than that of a conventional car body conveyor.Furthermore the centrally located friction bars 114 and roller driveensure stable travel of the carrier frames 111 and enable theconstruction of the skid-type carrier 110 to be simplified. Thus, it isnot necessary to provide door opening-prevention ropes on the sides ofthe car body conveying paths X1 and X2, and therefore operating space isprovided on both sides of the conveying paths X1 and X2.

1. A transverse car body conveying system comprising: a pair of railsextending in spaced, parallel relation to each other along a conveyingpath; a skid-type carrier supported on said rails for travel along saidconveying path; brackets on said skid-type carrier arranged to supportan elongated car body on said carrier, with the direction of elongationof said car body extending transverse to the direction of travel of thecarrier along said conveying path; a friction bar supported by saidcarrier and extending along the direction of travel of the carrier alongsaid conveying path; and a drive roller disposed on said conveying pathand positioned to engage, and impart a frictional driving force to, saidfriction bar.
 2. A transverse car body conveying system according toclaim 1, including an elongated car body supported on said brackets withthe direction of elongation of the car body extending transverse to thedirection of travel of the carrier along said conveying path.
 3. Atransverse car body conveying system according to claim 2, in which thelength of said friction bar is greater than the maximum width of the carbody but less than the length of said car body.
 4. A transverse car bodyconveying system according to claim 1, in which said friction bar andsaid drive roller are located along a center line midway between saidrails.
 5. A transverse car body conveying system according to claim 1,in which said car body has doors, including door opening-preventionbarriers at front and rear positions on said skid-type carrier, saidbarriers being positioned to engage doors of a car body supported onsaid carrier to limit opening thereof.
 6. A transverse car bodyconveying system according to claim 2, in which said car body has doors,and including door opening-prevention barriers at front and rearpositions on said skid-type carrier, said barriers being positioned toengage said doors of the car body to limit opening thereof.
 7. Atransverse car body conveying system according to claim 3, in which saidcar body has doors, and including door opening-prevention barriers atfront and rear positions on said skid-type carrier, said barriers beingpositioned to engage said doors of the car body to limit openingthereof.
 8. A transverse car body conveying system according to claim 4,including door opening-prevention barriers at front and rear positionson said skid-type carrier, said barriers being positioned to engagedoors of a car body supported on said carrier to limit opening thereof.